Graft placement system and method

ABSTRACT

Embodiments of the invention include a system and method for coupling a graft to a bone. A graft preparation tool may be used to place one or more holes in a graft and an offset measurement tool may be used to determine the distance of the one or more holes from an edge of the graft to be aligned with a portion of the bone. One or more complementary holes may then be created in the bone and fasteners applied through the holes to couple the graft to the bone.

FIELD OF THE INVENTION

The present invention relates generally to the field of placing graftswith surgical instruments, and more particularly relates to surgicalinstruments and methods used to align portions of a graft with a bone towhich the graft is to be coupled. Some embodiments include use of aspecially configured instrument to measure an offset from a hole in thegraft to a portion of the graft to be aligned with the bone.

BACKGROUND

Some surgical grafting procedures require that a graft be attached to abone in a very specific location. For example, where an edge or a faceof a graft is to be aligned with an edge or a face of a bone to whichthe graft is to be coupled to provide a bearing surface across the graftand the bone, alignment must be precise. In such circumstances, a systemand method for reliably and accurately placing the graft is needed. Oneexample of such a situation is a Latarjet protocol procedure, whichrequires that one or more holes be drilled into a severed piece of acoracoid graft and a glenoid. The respective hole or holes must alignsuch that placing one or more fasteners through the one or more holeswill fix a lateral edge of the coracoid graft flush with an articularsurface of the glenoid. The accurate placement of the one or more drillholes is critical to a successful alignment in a Latarjet protocolprocedure and many other procedures.

It would be advantageous to provide surgical instruments that providefor controlled placement of one or more holes through a graft and thatprovide for accurate measurement of the one or more holes as placedrelative to portions of a graft to be aligned with a bone to which thegraft is to be coupled. The instrument or instruments for enablingcontrolled placement of the holes may be separate from the instrument orinstruments for accurately measuring placement of the one or more holes.It may be further advantageous to provide a method that enable a surgeonto keep the graft separated from the bone to which the graft is to becoupled while one or more holes for fasteners are created in the bone sothat a clear view of the tissue into which a hole is being created maybe maintained during drilling. Some improved embodiments may include acollection or kit of multiple instruments and may also include implants.Such a collection or kit may promote efficient performance of graftalignment surgical procedures, such as but not limited to, Latarjetprotocol procedures.

SUMMARY

An embodiment of the invention is a system for coupling a graft to abone that may include a graft preparation tool, an offset measurementtool, and an offset drill guide. The graft preparation tool may includea holder in which a graft may be positioned, and a drilling alignmentmechanism configured to guide placement of one or more holes in a graft.The offset measurement tool may include a body and a pin with across-sectional center axis. The pin may be coupled to the body andsized to fit within at least one of the one or more holes in the graft.The offset measurement tool may also include two or more legs coupled tothe body and extending to two or more different distances from thecross-sectional center axis of the pin. The offset drill guide mayinclude a drill positioning opening, and an alignment surface set adistance from the drill positioning opening. The distance set from thedrill positioning opening is coordinated with the offset measured withthe offset measurement tool.

Another embodiment of the invention is an offset measurement tool thatincludes a body and a pin with a cross-sectional center axis, the pincoupled to the body and sized to fit within at least one of one or moreholes in a graft. Embodiments of the offset measurement tool may alsoinclude two or more legs coupled to the body and extending to two ormore different distances from the cross-sectional center axis of thepin.

Yet another embodiment of the invention is a method of performing aLatarjet protocol procedure. The method may include severing at least aportion of coracoid process from a patient, drilling one or more holesin the severed coracoid process, and providing an offset measurementtool. The offset measurement tool may include a body and a pin with across-sectional center axis, the pin coupled to the body. The pin may besized to fit within at least one of the one or more holes in the severedcoracoid process. The offset measurement tool may also include two ormore legs coupled to the body and extending to two or more differentdistances from the cross-sectional center axis of the pin. Methodembodiments may also include measuring an offset distance from a firstone of the holes in the severed coracoid process to an edge of thesevered coracoid process that is to be aligned with a face of a glenoidof the patient by inserting the pin of the offset measurement tool intothe first one of the holes in the severed coracoid process and observingwhich extent of one of the two or more legs most nearly aligns with theedge of the severed coracoid process that is to be aligned with a faceof a glenoid, the observation occurring when the offset measurement toolis rotated about the axis of the first one of the holes in the severedcoracoid process. Embodiments may additionally include selecting anoffset drill guide that correlates with the offset distance measuredfrom the first one of the holes in the severed coracoid process to anedge of the severed coracoid process with the offset measurement tool,aligning a portion of the offset drill guide with the face of theglenoid, and drilling a first hole in the glenoid through the offsetdrill guide. The first one of the holes in the severed coracoid processmay then be aligned with the first hole in the glenoid, and some methodembodiments include inserting a first screw through the first one of theholes in the severed coracoid process and through the first hole in theglenoid to couple the severed coracoid process to the glenoid.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an elevation view of an embodiment of a graft preparationtool.

FIG. 2 is an elevation view of the graft preparation tool of FIG. 1 inwhich a graft is being held.

FIG. 3 is a perspective view of an embodiment of an offset measurementtool.

FIG. 4 is a proximal end elevation view of the offset measurement toolof FIG. 3.

FIG. 5 is a perspective view of the offset measurement tool of FIG. 3being used to measure a graft held in the graft preparation tool of FIG.1.

FIG. 6 is an enlarged elevation view of the offset measurement tool inthe same position on the graft held by the graft preparation tool asshown in FIG. 5.

FIG. 7 is an elevation view of an embodiment of an offset drill guide.

FIG. 8 is an enlarged perspective view of a distal end of the offsetdrill guide illustrated in FIG. 7.

FIG. 9 is a perspective view of a partially exposed portion of apatient's right shoulder, including illustrations of a retractor and abone saw.

FIG. 10 is a perspective view of a patient's severed coracoid processbeing held in a position where it has been rotationally invertedapproximately 180 degrees about its generally longitudinal axis.

FIG. 11 is a perspective view of a patient's severed coracoid processbeing held in the graft preparation tool of FIG. 1 after beingrotationally inverted approximately 180 degrees about a distal lateralaxis of the severed coracoid process.

FIG. 12 is a perspective view of a patient's severed coracoid processbeing measured by the offset measurement tool of FIG. 3 after beingrotationally inverted approximately 180 degrees about its generallylongitudinal axis.

FIG. 13 is perspective view illustrating preparation of a surface of apatient's glenoid to which a graft is to be coupled.

FIG. 14 is perspective view of the offset drill guide of FIG. 7 inposition for a hole to be drilled in the prepared glenoid illustrated inFIG. 13.

FIG. 15 is perspective view of a patient's severed coracoid processthrough which a first screw has been placed after being aligned with ahole drilled in the glenoid with the offset drill guide, as shown inFIG. 14.

FIG. 16 is a perspective view of a second screw being place through apatient's coracoid process and into the patient's glenoid.

DETAILED DESCRIPTION

A system for coupling a graft to a bone is illustrated in FIGS. 1-8. Thesystem is shown being used to perform a method embodiment in FIGS. 9-16.A graft 1 illustrated in FIGS. 2, 5, 6, 9-12, 15, and 16 is a severedportion of a coracoid process. In other embodiments, the graft may beany other natural or synthetic graft material that may be accepted in apatient's body. For example and without limitation, a graft may be anautograft from another portion of a patient's body, an allograft, axenograft, a tricalcium phosphate graft, or a metal or polymer implant.

A graft preparation tool 100 that includes a holder 110 and a drillingalignment mechanism 120 is shown in FIGS. 1, 2, 5, 6, and 11. The holder110 depicted is configured to receive the graft 1 in textured jaws 115that clamp the graft 1 in a position. In other embodiments, a holder maynot clamp the graft, but may merely contain the graft while the graft isprepared. The holder 110 shown is a singly hinged plyer-type mechanismthat brings the textured jaws 115 together about a single pivot pin 117(FIG. 5). In other embodiments, a holder may include additional linkagesthat cause faces of jaws to move relative to one another in a parallelrelationship so that grafts of various widths may be clamped betweenparallel faces of the jaws by a common instrument. A thread-driven vicemay be used to clamp a graft within a holder of some embodiments. Anyother mechanisms that effectively contain or clamp a graft forpreparation may be used in other embodiments. Jaws of some embodimentsare not necessarily textured or may include different types of texturingfrom the generally pyramid shapes shown. A locking bolt 160 isillustrated in FIGS. 1, 2, and 5 which may be used to lock the graftpreparation tool 100 in a closed position. Other embodiments may includeany type of effective locking mechanism.

The drilling alignment mechanism 120 is configured to guide placement ofone or more holes in the graft 1. The drilling alignment mechanism 120shown includes three drill guiding holes 123 through which a drill bit173 (FIG. 11) coupled with a drill 170 may be advanced to create one ormore holes in the graft 1. The drill guiding holes 123 are configured toposition placement of holes in the graft 1 by providing guides alongrespective axes of the drill guiding holes 123. With predetermineddistance relationships among the three drill guiding holes 123, threedifferently spaced pairs of holes may be drilled through the drillguiding holes 123. For example, in the illustrated embodiment, thedistance between the most distal and the center drill guiding holes 123is 10 mm. Therefore, drilling through the center drill guide hole (FIG.11) and the distal drill guiding hole will create substantially parallelholes in the graft 1 that are 10 mm apart. Other numbers of drillguiding holes or adjustable guide mechanisms may be used in otherembodiments. Any other effective guiding or hole creation mechanism maybe used in various embodiments. The drilling alignment mechanism 120illustrated is movable relative to the holder 110. A knob 125 isconfigured to be tightened and loosened to restrict or permit movementof the drilling alignment mechanism 120 relative to the holder 110. Asshown in FIG. 1, the drilling alignment mechanism 120 may be movedoutside of the opening between the textured jaws 115 of the holder 110.Or as shown in FIGS. 2 and 11, the alignment mechanism 120 may bepositioned between and adjacent to the opening between the textured jaw115 when a graft 1 is being held in the holder 110 to guide drillinginto the graft 1. Other types of relative adjustment between a holderand guiding mechanism may be used in other embodiments.

An offset measurement tool 200 is illustrated in FIGS. 3-6 and 12. Theoffset measurement tool 200 may be a part of a system for coupling agraft to a bone or may be a discrete instrument used to measure forplacement of a graft or for other measurement purposes. The offsetmeasurement tool 200, as shown specifically in FIGS. 3 and 4, includes abody 201, a pin 203 coupled to the body 201, and two or more legs 205,206, 207, 208 coupled to the body 201. The body 201 illustrated isgenerally elongated cylindrical rod. However, other embodiments mayinclude any effective shape or proportion to which a pin and legs may becoupled to accomplish measurement of an offset.

The pin 203 has a cross-sectional center axis that is aligned with acentral longitudinal axis of the body 201. The pin 203 is sized to fitwithin at least one of the one or more holes in a graft. In particularfor the illustrated embodiment, the pin 203 is sized to fit within anyof the holes 5 drilled in the graft 1 through the drill guiding holes123. A more distal hole 5 is visible in FIGS. 5 and 6, and a moreproximal hole 5, having received the pin 203 of the offset measurementtool 200, is not visible in the illustrations. The pin 203 depicted hasa circular cross-section. However, other embodiments may include anyeffective shape that would serve as a temporary fixation mechanismbetween a measurement tool and a graft. For example and withoutlimitation, the cross-sectional shape of a pin of other embodiments maybe square, triangular, rectangular, a higher number of sides polygon,star-shaped, or keyed to fit within a particularly configured holecreated in a graft.

Legs 205, 206, 207, 208 illustrate a set of two or more legs coupled tothe body 201 and extending to two or more distances from thecross-sectional center axis of the pin 203. The distances of theillustrated embodiment are lateral from and measured perpendicular to acentral longitudinal axis through the cross-sectional center axis of thepin 203. In some embodiments, legs could be considered to be coupled toa pin rather than to a body, and to the extent that a cross-sectionalcenter axis of the pin and a central longitudinal axis of a body areco-linear, distances measured laterally from and perpendicular to thelongitudinal axis of the body and the cross-sectional center axis of thepin would be the same respective distances. The legs 205, 206, 207, 208extend from the cross-sectional center axis of the pin 203 to therespective extents of the four legs about 5 mm, 6 mm, 7 mm, and 8 mm.The legs 205, 206, 207, 208 shown are each about 1 mm differentdistances from the cross-sectional center axis to their respectiveextents. Other embodiments may include any effective lengths of legswhich may be at 1 mm intervals relative to one another or any otherinterval, and may includes uses of other units of measure. The legs 205,206, 207, 208 depicted in FIGS. 4, 6, and 12 include numbers (“5”, “6”,“7”, and “8”) written on the legs 205, 206, 207, 208 that correspondwith the distance from the cross-sectional center axis of the pin 203 tothe extent of each of the legs on which the respective numbers arewritten. As illustrated, each of the numbers written is viewable frombeyond a proximal end of the offset measurement tool 200. In otherembodiments, some but not all numbers corresponding to length may bewritten on respective legs. In addition or in the alternative, colors,textures, or any other encoding or indicators may be used to designaterespective lengths. In some embodiments, corresponding lengths may beincluded on proximal portions of an offset measurement tool such that awritten length number may be associated with a rotational position of anoffset measurement tool without viewing a number written directly on aleg.

The legs 205, 206, 207, 208 illustrated are each considered to extendsubstantially radially from the cross-sectional center axis of the pin203. Each of the legs 205, 206, 207, 208 is substantially perpendicularto each leg adjacent to the leg. For example, the leg 207 issubstantially perpendicular to legs 206 and 208, leg 208 issubstantially perpendicular to legs 205 and 207, and so on. In otherembodiments, there may be more or fewer legs coupled to a body andextending to distances from the cross-sectional center axis of a pin.For example and without limitation, there may be one, two, three, five,or more legs. Each of the legs may include a separate radially extendingstructure, as shown with the present embodiment, or what are consideredto be legs may be interconnected portions of one or more shapes coupledto a body. The legs of other embodiments may be spaced radiallyequidistantly from one another, as are the legs 205, 206, 207, 208, ormay include partially or thoroughly irregular spacing.

Embodiments of the system for coupling a graft may also include anoffset drill guide. An example offset drill guide 300 is illustrated inFIGS. 7, 8, and 14. The offset drill guide 300 shown includes a drillpositioning opening 310 through a guide tube 315 and an alignmentsurface 320 set a distance from the drill positioning opening 310. Inthe embodiment shown, the set distance “A” is 7 mm from the alignmentsurface 320 to the central longitudinal axis or cross-sectional centerof the drill positioning opening 310 and guide tube 315. In otherembodiments where a drill positioning opening is not central to a guidetube central axis, the set distance may be measured between thealignment surface and the cross-sectional center of the drillpositioning opening or similar location corresponding with where a holewill be created through an offset drill guide. The offset drill guide300 is coordinated for use with the 7 mm offset measured with the offsetmeasurement tool 200 in FIGS. 5, 6, and 12. Embodiments of the systemfor coupling a graft may include a set of offset drill guides that arecoordinated with each of the potential offsets that may be measured withan offset measurement tool. One or more additional offset drill guidesconfigured to be used to drill at distances estimated to be between ornear a measured offset may also be included as part of a system. Forexample and without limitation, a 6.5 mm offset drill guide could beincluded for use when a measurement appears to be between 6 mm and 7 mm.

Some embodiments of the system for coupling a graft may also include ina kit, or may separately provide, the drill 170 and one or more drillbits. The example drill bit 173 is shown coupled to the drill 170 inFIG. 11. Different size drill bits and different styles of drills may beused in some embodiments. A drill may be a rotary power drill asdepicted in the example of the drill 170 or may be any other effectivetool, however powered or driven, capable of assisting with the creationof a hole. Likewise, a drill bit or similar device of other embodimentsmay be any type of mechanism useful in creation of a hole. Someembodiments of the system for coupling a graft may also include a guidepin that may be used to define a path between a hole in a graft and ahole in a bone to which the graft is to be connected for the purpose ofalignment. A guide pin may also be used in combination with a cannulatedfastener sized to fit over the guide pin and be directed by the guidepin to a desired implantation location through one or both of the graftand the bone to which the graft is to be connected. An example firstscrew 61 is shown in FIGS. 15 and 16 along with a driver 65. An examplesecond screw 62 is depicted in FIG. 16. These or any other effectivefastener and driver or inserter may be used in other embodiments.

An embodiment of the invention may include a kit that contains two ormore of a graft preparation tool, an offset measurement tool, an offsetdrill guide, a drill, a drill bit, a screw, a driver, and a guide pin. Akit may include two or more of each of these components, each in thesame size or in a variety of sizes as may promote efficient performanceof graft alignment surgical procedures.

A depiction of a method embodiment of the invention is illustrated inFIGS. 9-16. The particular method illustrated is a Latarjet protocolprocedure. However, similar graft preparation, anatomical preparation,graft to bone alignment, and graft to bone coupling may be accomplishedat other locations and for other purposes. A perspective view of apartially exposed portion of a patient's right shoulder is shown in FIG.9. A retractor 3 and a bone saw 40 are also shown in FIG. 9. Retractorsof any effective type may be used and retractors of other sizes andtypes are shown in appropriate use herein without further explanation.The bone saw 40 is shown with an end-cutting blade aligned to cut acoracoid process or graft 1 along a projection line 11. In theillustrated method, a conjoined tendon 2 near a distal end of the graft1 is left intact. Method embodiments include severing at least a portionof the severed coracoid process from a patient. The graft 1 of theillustrated embodiment may be referred to throughout either as the graft1 or as the severed coracoid process. Cutting of a coracoid process maybe accomplished with the bone saw 40 or by use of any other effectivedevice or method. A patient's severed coracoid process is shown beingheld in a position with a clamp 50 where the severed coracoid processhas been rotationally inverted approximately 180 degrees about itsgenerally longitudinal axis in FIG. 10.

An act of some embodiments is the drilling of one or more holes throughthe graft 1. In some embodiments, soft tissues are removed from thegraft 1 at least on a side that is to be coupled to bone. Holes forfasteners may be created in or through the graft 1. In FIG. 11, thesevered coracoid process is shown being held in the graft preparationtool 100 that includes the holder 110 and the drilling alignmentmechanism 120 that is coupled to the holder 110. As described in detailherein, the drilling alignment mechanism 120 is adjustably coupled tothe holder 110 and includes the drill guiding holes 123 to directdrilling of the holes 5 (FIGS. 5 and 6) through the graft 1. Thedrilling of a hole 5 in the graft 1 is being shown in FIG. 11 with thedrill bit 173 being rotated by the drill 170. In the illustratedembodiment, the graft 1 is held in the graft preparation tool 100 afterbeing rotationally inverted approximately 180 degrees about a distallateral axis of the graft 1. Drilling or creating of holes through asevered coracoid process or another graft of other embodiments is notnecessarily accomplished with the use of the graft preparation tool 100,but in some circumstances may be.

As shown in FIG. 12, the offset measurement tool 200 may be provided foruse in determining an offset distance from a hole in the severedcoracoid process to an edge 81 of the severed coracoid process. Theoffset measurement tool provided may be the same as the offsetmeasurement tool 200 or similar devices described in detail herein. Someembodiments may include the use of an alternative offset measurementtool. The graft 1 is shown being measured in FIG. 12 by the offsetmeasurement tool 200 after being rotationally inverted approximately 180degrees about its generally longitudinal axis. Method embodiments mayalso include the act of measuring an offset distance from a first hole 5in the graft 1 to the edge 81 (FIGS. 6, 12, 15, and 16) of the graft 1that is to be aligned with a face 91 of a glenoid 10 by inserting thepin 203 (FIG. 3) of the offset measurement tool 200 into the first oneof the holes 5 in the graft 1 and observing which extent of one of thetwo or more legs 205, 206, 207, 208 most nearly aligns with the edge 81of the graft 1 that is to be aligned with the face 91 of the glenoid 10.As can be seen in FIG. 12, the leg 207 most nearly aligns with the edge81 of the graft 1 that is to be aligned with the face 91 of the glenoid10. In some embodiments, such an observation occurs when an offsetmeasurement tool is rotated about the axis of the hole in the graft inwhich the offset measurement tool is inserted. For example, the offsetmeasurement tool 200 is rotated in the more distal hole 5 while anobservation regarding alignment of an extent of a leg 205, 206, 207, 208relative to the edge 81 of the graft 1 is made. By observation, it isnoted that the leg 207, with an offset distance of 7 mm, most nearlyaligns with the edge 81 of the graft 1 that is to be aligned with theface 91 of the glenoid 10. In the illustrated embodiment the act ofmeasuring an offset distance includes observing a number written on theleg—in this case the number “7” on the leg 207. As shown, the leg 207most nearly aligns with the edge 81 of the graft 1 that is to be alignedwith the face 91 of the glenoid 10. In other embodiments, whichevernumber or other indicator associated with the extent of whichever legmost nearly aligns with the edge 81 of the graft 1 that is to be alignedwith the face 91 of the glenoid 10 would similarly be noted. In thedisclosed embodiment, the number is viewable from beyond a proximal endof the offset measurement tool 200. In this or other embodiments such anumber or another indicator may also be viewable through a tube, aretractor, an endoscope, or other viewing device. In some embodiments,numbers or other indicators may be included on proximal portions of anoffset measurement tool such that the numbers or indicators may beassociated with a rotational position of an offset measurement toolwithout viewing a number written directly on a leg or at a distal end ofan offset measurement tool.

Some method embodiments include preparing a bone to receive a graft. Aprepared glenoid surface 12 of the glenoid 10 to which a graft may becoupled is shown in FIG. 13. An articular proximal surface of a humerus20 is also illustrated in FIGS. 13 and 14. In the embodiment shown, softtissues and an outer portion of the glenoid 10 have been removed toexpose bleeding bone and to expose an edge along the face 91 of theglenoid 10.

An act of some method embodiments also includes selecting an offsetdrill guide that correlates with the offset distance measured from oneof the holes 5 in the graft 1 to an edge 81 of the graft 1 with theoffset measurement tool 200. The offset drill guide 300 shown in FIGS.7, 8, and 14 includes a 7 mm offset distance and was selected for use inthe current embodiment because of correlation with the 7 mm offsetmeasured with the offset measurement tool 200, as shown in FIGS. 6 and12. As shown in FIG. 14 the offset drill guide 300 may be aligned withthe face of the glenoid 10, and a first hole may be drilled into theprepared glenoid surface 12. More specifically in the illustratedembodiment, the alignment surface 320 (FIGS. 7, 8, and 14) is alignedwith the face of the glenoid 10. This positioning properly sets thedistance from the face of the glenoid 10 and then a surgeon may placethe offset drill guide 300 along a line generally parallel with the faceof the glenoid 10 prior to drilling through the offset drill guide 300.

Method embodiments may also include aligning one of the holes in thegraft 1 with one of the holes created in the glenoid 10. For example,the more distal hole 5 in the graft 1 may be aligned with the holecreated in the glenoid 10 shown being set for drilling in FIG. 14.Alignment may be accomplished with the assistance of a guide wire thatis extended through both the more distal hole 5 and the hole created inthe glenoid 10. The graft 1 may then be held in the aligned positionwhile the first screw 61 (FIGS. 15 and 16) is inserted. In anotherembodiment, the first screw 61 may be partially advanced through a holein the graft 1, as shown in FIG. 15, and the first screw 61 itself maybe used to align the more distal hole 5 with the hole created in theglenoid 10. Other embodiments may include any other effective mechanismor means of alignment and screw placement. The first screw 61 may thenbe advanced to couple the graft 1 to the glenoid 10. In the embodimentshown, the driver 65 is used to rotate and advance the first screw 61.The first screw 61 may be the only fastener used in some embodiments.The first screw 61 may be fully advanced prior to any subsequent screwsbeing implanted or may be partially advanced to allow for continuedadjustment of the graft 1 relative to the glenoid 10 during theprocedure.

The second screw 62 is shown being inserted through the graft 1 and intothe glenoid 10 in FIG. 16. There at least two ways of drilling for andinserting the second screw 62. One way of placing the second screw 62includes aligning the edge 81 of the graft 1 with the face 91 of theglenoid 10 and drilling a second hole in the prepared glenoid surface 12(FIGS. 13-15) of the glenoid 10 through a second one of the holes in thegraft 1. For example, with the graft 1 in the position shown in FIG. 16,a second hole in the glenoid 10 may be drilled through the more proximalhole 5 (FIG. 6) in the graft 1 prior to a inserting the second screw 62through the graft 1 and into the second hole in the glenoid 10.

Another way of placing the second screw 62 includes using the offsetmeasurement tool 200 to preplan the placement of the second screw 62based on measurements taken prior to inserting the first screw 61through the graft 1. This method may include measuring an offsetdistance from a second one of the holes 5 in the graft 1 to an edge 82(FIG. 6) of the graft 1 that is to be aligned with a face 91 of aglenoid 10. This measurement may be accomplished by inserting the pin203 of the offset measurement tool 200 into the second one of the holes5 in the graft 1 and observing which extent of one of the two or morelegs 205, 206, 207, 208 most nearly aligns with the edge 82 of the graft1 that is to be aligned with the face 91 of the glenoid 10 when theoffset measurement tool 200 is rotated about the axis of the second oneof the holes 5 in the graft 1. This method embodiment may also includeselecting an offset drill guide, such as the offset drill guide 300,that correlates with the offset distance measured from the second one ofthe holes 5 in the graft 1 to an edge 82 of the graft 1 by measuringwith the offset measurement tool 200. The offset drill guide 300 maythen be aligned with the face 91 of the glenoid 10 at an appropriatelinear distance away from the first one of the holes 5 in the graft 1.The appropriate linear distance may be established with a linkageconfigured for insertion in the first one of the holes 5 and rotatablecoupling with the appropriate offset drill guide. A second hole may thenbe drilled in the glenoid 10 through the offset drill guide with theappropriate amount of offset. Such a method embodiment may subsequentlyinclude aligning the second one of the holes 5 in the graft 1 with thesecond hole in the glenoid 10, and inserting the second screw 62 throughthe second one of the holes 5 in the graft 1 and through the second holein the glenoid 10 to couple the graft 1 to the glenoid 10.

Various embodiments of a system wholly or its components individuallymay be made from any biocompatible material. For example and withoutlimitation, biocompatible materials may include in whole or in part:non-reinforced polymers, reinforced polymers, metals, ceramics,adhesives, reinforced adhesives, and combinations of these materials.Reinforcing of polymers may be accomplished with carbon, metal, or glassor any other effective material. Examples of biocompatible polymermaterials include polyamide base resins, polyethylene, Ultra HighMolecular Weight (UHMW) polyethylene, low density polyethylene,polymethylmethacrylate (PMMA), polyetheretherketone (PEEK),polyetherketoneketone (PEKK), a polymeric hydroxyethylmethacrylate(PHEMA), and polyurethane, any of which may be reinforced. Examplebiocompatible metals include stainless steel and other steel alloys,cobalt chrome alloys, zirconium, oxidized zirconium, tantalum, titanium,titanium alloys, titanium-nickel alloys such as Nitinol and othersuperelastic or shape-memory metal alloys.

Terms such as distal, proximal, over, near, and the like have been usedrelatively herein. However, such terms are not limited to specificcoordinate orientations, distances, or sizes, but are used to describerelative positions referencing particular embodiments. Such terms arenot generally limiting to the scope of the claims made herein. Anyembodiment or feature of any section, portion, or any other componentshown or particularly described in relation to various embodiments ofsimilar sections, portions, or components herein may be interchangeablyapplied to any other similar embodiment or feature shown or describedherein.

While embodiments of the invention have been illustrated and describedin detail in the disclosure, the disclosure is to be considered asillustrative and not restrictive in character. All changes andmodifications that come within the spirit of the invention are to beconsidered within the scope of the disclosure.

What is claimed is:
 1. A system for coupling a graft to a bonecomprising: a graft preparation tool comprising: a holder in which agraft may be positioned, and a drilling alignment mechanism configuredto guide placement of one or more holes in a graft; an offsetmeasurement tool comprising: a body, a pin with a cross-sectional centeraxis, the pin coupled to the body, wherein the pin is sized to fitwithin at least one of the one or more holes in the graft, and two ormore legs coupled to the body and extending to two or more differentdistances from the cross-sectional center axis of the pin; and an offsetdrill guide comprising: a drill positioning opening, and an alignmentsurface set a distance from the drill positioning opening, wherein thedistance set from the drill positioning opening is coordinated with theoffset measured with the offset measurement tool.
 2. The system of claim1 wherein the holder is a clamp.
 3. The system of claim 1 wherein thedrilling alignment mechanism is movable relative to the holder.
 4. Thesystem of claim 1 wherein the drilling alignment mechanism includes twoor more holes in a predetermined relationship to one another and whereinthe two or more holes are configured to position placement of holes inthe graft by providing guides for drilling along respective axes of thetwo or more holes.
 5. The system of claim 1 wherein the pin has acircular cross-section.
 6. The system of claim 1 wherein the two or morelegs extend substantially radially from the cross-sectional center axisof the pin.
 7. The system of claim 1 wherein there are four legs coupledto the body.
 8. The system of claim 7 wherein each of the four legsextends substantially radially from the cross-sectional center axis ofthe pin and each of the four legs is substantially perpendicular to eachleg adjacent to the leg.
 9. The system of claim 7 wherein the respectivedistances from the cross-sectional center axis of the pin to therespective extents of the four legs are about 5 mm, 6 mm, 7 mm, and 8mm.
 10. The system of claim 1 wherein the two or more differentdistances from the cross-sectional center axis are each about 1 mmdifferent from one or more of the other distances.
 11. The system ofclaim 1, further comprising one or more numbers written on one or moreof the two or more legs that correspond with the distance from thecross-sectional center axis of the pin to the extent of the leg on whichthe number is written.
 12. The system of claim 11 wherein the one ormore numbers are viewable from beyond a proximal end of the offsetmeasurement tool.
 13. The system of claim 1, further comprising a drilland a drill bit.
 14. An offset measurement tool comprising: a body; apin with a cross-sectional center axis, the pin coupled to the body,wherein the pin is sized to fit within at least one of one or more holesin a graft; and two or more legs coupled to the body and extending totwo or more different distances from the cross-sectional center axis ofthe pin.
 15. The offset measurement tool of claim 14 wherein the pin hasa circular cross-section.
 16. The offset measurement tool of claim 14wherein the two or more legs extend substantially radially from thecross-sectional center axis of the pin.
 17. The offset measurement toolof claim 14 wherein there are four legs coupled to the body.
 18. Theoffset measurement tool of claim 17 wherein each of the four legsextends substantially radially from the cross-sectional center axis ofthe pin and each of the four legs is substantially perpendicular to eachleg adjacent to the leg.
 19. The offset measurement tool of claim 17wherein the respective distances from the cross-sectional center axis ofthe pin to the respective extents of the four legs are about 5 mm, 6 mm,7 mm, and 8 mm.
 20. The offset measurement tool of claim 14 wherein thetwo or more different distances from the cross-sectional center axis areeach about 1 mm different from one or more of the other distances. 21.The offset measurement tool of claim 14, further comprising one or morenumbers written on one or more of the two or more legs that correspondwith the distance from the cross-sectional center axis of the pin to theextent of the leg on which the number is written.
 22. The offsetmeasurement tool of claim 21 wherein the one or more numbers areviewable from beyond a proximal end of the offset measurement tool. 23.A method of performing a Latarjet protocol procedure comprising:severing at least a portion of a coracoid process from a patient;drilling one or more holes in the severed coracoid process; providing anoffset measurement tool comprising: a body, a pin with a cross-sectionalcenter axis, the pin coupled to the body, wherein the pin is sized tofit within at least one of the one or more holes in the severed coracoidprocess, and two or more legs coupled to the body and extending to twoor more different distances from the cross-sectional center axis of thepin; measuring an offset distance from a first one of the holes in thesevered coracoid process to an edge of the severed coracoid process thatis to be aligned with a face of a glenoid of the patient by insertingthe pin of the offset measurement tool into the first one of the holesin the severed coracoid process and observing which extent of one of thetwo or more legs most nearly aligns with the edge of the severedcoracoid process that is to be aligned with a face of a glenoid, theobservation occurring when the offset measurement tool is rotated aboutthe axis of the first one of the holes in the severed coracoid process;selecting an offset drill guide that correlates with the offset distancemeasured from the first one of the holes in the severed coracoid processto an edge of the severed coracoid process with the offset measurementtool; aligning a portion of the offset drill guide with the face of theglenoid; drilling a first hole in the glenoid through the offset drillguide; aligning the first one of the holes in the severed coracoidprocess with the first hole in the glenoid; and inserting a first screwthrough the first one of the holes in the severed coracoid process andthrough the first hole in the glenoid to couple the severed coracoidprocess to the glenoid.
 24. The method of claim 23 wherein the act ofsevering a least a portion of a coracoid process does not includeremoving a conjoined tendon near a distal end of the severed coracoidprocess from the severed coracoid process.
 25. The method of claim 23wherein the act of drilling one or more holes through the severedcoracoid process includes holding the severed coracoid process in agraft preparation tool that includes a holder and a drilling alignmentmechanism that is coupled to the holder, wherein the drilling alignmentmechanism is adjustably coupled to the holder and includes drillingguides to direct drilling of holes through the severed coracoid process.26. The method of claim 23 wherein the act of measuring an offsetdistance includes observing which extent of one of the legs coupled tothe body most nearly aligns with the edge of the severed coracoidprocess that is to be aligned with the face of the glenoid.
 27. Themethod of claim 23 wherein the act of measuring an offset distanceincludes observing a number written on the leg that includes an extentthat most nearly aligns with the edge of the severed coracoid processthat is to be aligned with the face of the glenoid.
 28. The method ofclaim 27 wherein the act of observing a number written on the leg thatincludes an extent that most nearly aligns with the edge of the severedcoracoid process that is to be aligned with the face of the glenoidincludes viewing the number from beyond a proximal end of the offsetmeasurement tool.
 29. The method of claim 23 wherein the act of aligningthe first one of the holes in the severed coracoid process with thefirst hole in the glenoid includes placing a guide wire through thefirst one of the holes in the severed coracoid process and the firsthole in the glenoid.
 30. The method of claim 23, further comprisingremoving a portion of soft tissue from the severed coracoid processwhere the severed coracoid process will contact the glenoid to becoupled with the glenoid.
 31. The method of claim 23, furthercomprising: aligning the edge of the severed coracoid process with theface of the glenoid; drilling a second hole in the glenoid through asecond one of the holes in the severed coracoid process; and inserting asecond screw through the second one of the holes in the severed coracoidprocess and through the second hole in the glenoid to couple the severedcoracoid process to the glenoid.
 32. The method of claim 23, furthercomprising: measuring an offset distance from a second one of the holesin the severed coracoid process to an edge of the severed coracoidprocess that is to be aligned with a face of a glenoid of the patient byinserting the pin of the offset measurement tool into the second one ofthe holes in the severed coracoid process and observing which extent ofone of the two or more legs most nearly aligns with the edge of thesevered coracoid process that is to be aligned with the face of theglenoid when the offset measurement tool is rotated about the axis ofthe second one of the holes in the severed coracoid process; selectingan offset drill guide that correlates with the offset distance measuredfrom the second one of the holes in the severed coracoid process to anedge of the severed coracoid process with the offset measurement tool;aligning a portion of the offset drill guide with the face of theglenoid; drilling a second hole in the glenoid through the offset drillguide; aligning the second one of the holes in the severed coracoidprocess with the second hole in the glenoid; and inserting a secondscrew through the second one of the holes in the severed coracoidprocess and through the second hole in the glenoid to couple the severedcoracoid process to the glenoid.